Researchers at the Johns Hopkins Bloomberg School of Public Health have, for the first time, shown that infection with dengue virus turns on mosquito genes that makes them hungrier and better feeders, and therefore possibly more likely to spread the disease to humans. Specifically, they found that dengue virus infection of the mosquito's salivary gland triggered a response that involved genes of the insect's immune system, feeding behavior and the mosquito's ability to sense odors. The researchers findings are published in the March 29 edition of PLoS Pathogens.
Dengue virus is primarily spread to people by the mosquito Aedes aegypti. Over 2.5 billion people live in areas where dengue fever is endemic. The World Health Organization estimates that there are between 50 million and 100 million dengue infections each year.
"Our study shows that the dengue virus infects mosquito organs, the salivary glands and antennae that are essential for finding and feeding on a human host. This infection induces odorant-binding protein genes, which enable the mosquito to sense odors. The virus may, therefore, facilitate the mosquito's host-seeking ability, and could?at least theoretically?increase transmission efficiency, although we don't fully understand the relationships between feeding efficiency and virus transmission," said George Dimopoulus, PhD, senior author of the study and professor with the Bloomberg School's Malaria Research Institute. "In other words, a hungrier mosquito with a better ability to sense food is more likely to spread dengue virus."
For the study, researchers performed a genome-wide microarray gene expression analysis of dengue-infected mosquitoes. Infection regulated 147 genes with predicted functions in various processes including virus transmission, immunity, blood-feeding and host-seeking. Further analysis of infected mosquitoes showed that silencing, or "switching off," two odorant-binding protein genes resulted in an overall reduction in the mosquito's blood-acquisition capacity from a single host by increasing the time it took the for mosquito to probe for a meal.
"We have, for the first time shown, that a human pathogen can modulate feeding-related genes and behavior of its vector mosquito, and the impact of this on transmission of disease could be significant," said Dimopoulos.
"Dengue virus infection of the Aedes aegypti salivary gland and chemosensory apparatus induces genes that modulate infection and blood-feeding behavior" was written by Shuzhen Sim, Jose L. Ramirez and George Dimopoulos.
###
Johns Hopkins University Bloomberg School of Public Health: http://www.jhsph.edu
Thanks to Johns Hopkins University Bloomberg School of Public Health for this article.
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
This press release has been viewed 27 time(s).
national enquirer whitney houston arizona republican debate arizona debate enquirer national inquirer knicks vs heat ash wednesday
Recently my personal cyberspace has been inundated with blurbs about the so-called Republican ?War on Women,? mostly having to do with a conservative-led challenge to a national mandate that employers with religious objections to contraception and abortion be required to pay for insurance coverage for these services. It?s a genuine Constitutional issue. Freedom of conscience is an important safeguard against steamroller tactics propelling a society towards an enticing but ultimately disastrous trajectory. But somehow the messages that appear on bulletin boards assume that women have a right to compel others to pay for a particular form of contraception, and that this overrides the personal moral qualms of a nontrivial proportion of the population.
![[ Back to EurekAlert! ]](http://www.eurekalert.org/images/back2e.gif){kind=small}
Public release date: 13-Mar-2012
Share ] 
If my life is a library, I have a whole section for adoption. Every year for my adoption day, my parents gave me a book inscribed with a message of praise and gratitude that I came into their lives. The first book I remember is a pen-and-ink picture book of a monkey at a birthday party with a trombone. And there?s the one my father read aloud to us after dinner that had my name in the first sentence. The small book of poems about nature that made me start writing. A cookbook I?ve used so much that the pages stick together with floury glue. Novels, nonfiction; cardstock, coffee table; banal, beautiful. To date I have 37 books scattered between my home and my mother?s house, each a thank you note for the miracle of adoption in our family.
Another metaphoric shelf in my library houses the books I was reading when I was unexpectedly pregnant and looking for a family for my birthson. The week after I discovered I was pregnant, I bought What to Expect When You?re Expecting, the classic book for mothers-to-be. I no longer have the book?I gave it to a friend after a few years?but I can still see the picture of the pregnant woman on the front, reading and smiling in a nursery rocking chair. I was glad to have a book about pregnancy, but felt ostracized when I couldn?t find any books that dealt with the challenges of placing a baby for adoption. At least not books with positive messages. There was a definite empty space on my shelves for books that could have helped me weather the challenges and emotions of becoming a birthmother.
So what section of the library am I in now? I?m in the waiting room. My partner and I are waiting to adopt? a baby of our own. Although it?s only been eight months, it feels like an eternity when you?re waiting for a baby. It could happen any minute. And it could happen five years from now. As we wait, the books are piling up. Our mahogany hope chest is full of baby books: two copies of Goodnight Moon, books about sea turtles to use in the bath, books about animals and trucks and children and nature and everything we want to teach our children. And books about adoption. Right now we are living in an age when people can talk about the adoption process without shame or stigma. There are books on how to talk to other people about your adoption journey, the specific challenges and joys transracial adoption brings, advice for staying in touch with your children?s birthmother, how to find adoption groups so your kids can have play dates with other adoptees, how to talk to your kids about other kinds of families.
The world has really opened up about adoption in the decades since my adoption and since my birthson?s adoption. I?m fortunate, and my children will be fortunate, to live in a time when adoption is simply one of the many ways of creating a family. In any library, you?ll find books about single parent families, grandparent families, gay families, foster families, stay-at-home parent families, divorced families, blended families? Each of us has an internal library, space for all of the stories of our lives, and more and more we can find ourselves represented on actual shelves.